The statements in this section merely provide background information related to the present disclosure and do not necessarily constitute prior art.
A signal transmission method based on an optical fiber, which is widely used in a long haul communication, is in widespread use for a large-capacity digital media transmission including a high-definition digital video display for which high-speed and high-density data transmission is required, owing to the operation characteristics unaffected by an electromagnetic interference (EMI) and usefulness in a broad bandwidth of the optical fiber.
Such a signal transmission method based on the optical fiber can be implemented by arranging a lens and a reflecting member configured between an optical fiber and an optical element. One possible way to achieve such configuration is to install the optical fiber and a structure affixed with the reflecting member and the lens on a substrate mounted with the optical element to establish an optical alignment.
This method of optical alignment can be incorporated into manufacturing an optical transceiver, where a selected way of aligning the optical element, the lens, the reflecting member and the optical fiber dictates the structural simplification, manufacturing cost reduction, and durability and precision enhancements, etc., which exhibits the paramount significance of the optical alignment issue.
However, an optical transceiver manufactured by the optical alignment of the conventional method is not only highly costly but also too bulky to fit in a mobile communication apparatus such as a smartphone, and is troubled with instability issues due to a complicated structure.
FIG. 1 is a plan view of a typical optical transceiver device.
In FIG. 1, a substrate 101 is shown as mounted with an injection-molded structure 102. In general, the injection-molded structure 102 with precision holes is used as a guide because of the recognized difficulty of forming precision holes on the substrate 101 to mount another structure thereto. Optical elements 103 are disposed on the substrate 101. The substrate 101 includes two circular holes 104 formed in line with the arrangement of the optical elements 103, and the injection-molded structure 102 includes two round posts 105. The two round posts 105 are respectively inserted into the circular holes 104, and the optical alignment is achieved by further arranging a lens structure on the assembled injection-molded structure 102.
With the conventional technology, deviation of the optical alignment can be reduced to some extent; however, there still remain issues of complexity of assembling additional parts, inferior economic feasibility, and increased volume of the entire structure.
In addition, due to the nature of the structure that hardly provides the perfect fit in the coupling between the hole and the post as shown in FIG. 1, the hole and post affixed on one side lead to undesirable tolerances in the remaining hole and post on the other side. This leaves a certain amount of deviation in the optical alignment, which can cause critical technical issues in a field requiring a high level of precision.